The present invention relates to a change in the material composition of standard conventional fire hydrants. Current high pressure fire hydrants manufactured from grey or ductile iron can be advantageously manufactured with formulated polymers. These new hydrants will yield cost savings arising from minimizing manufacturing and maintenance labor in addition to gaining fabrication flexibility while minimizing manufacturing costs. Additional safety gains will accrue in the products use from reduced labor claims related to the lifting of heavy hydrants during installation and in the reduction of impact related claims.
The impetus for the dramatic change in the use of materials came from research into functionality flaws of conventional metallic hydrants manufactured in grey or ductile iron since the 1800's. One common characteristic of fire hydrants as currently manufactured is in the use of metal, but not limited to, gray and ductile iron as the preferred material type. The standard exterior installation scenario of these metallic hydrants makes them particularly susceptible to rusting, binding, cracking, and the need for repeated labor-intensive painting and maintenance efforts. Plastic hydrants can be manufactured with filled polymeric materials that are not only less expensive to manufacture and install but also resist the cumulative effects of all climatic influences such as ultra violet degradation, color fading, rusting, cracking, temperature effects and heat resistance.
Much development and disclosure has occurred independently for fire hydrants and water regulating and metering valves. For example, U.S. Pat. No. 154,087 issued toby C. H. Roberts on Aug. 11, 1874 discloses a hydrantteaches use of a supplementary valve for use during hydrant repairs. U.S. Pat. No. 3,104,554 issued to F. H. by Mueller and J. J. Smith on Sep. 24, 1963, discloses a fire hydrant teaches use of a removeable valve seat ring, improved valve sealing technologies, improved valve stem coupling and operating techniques and improved top plate securing techniques. Further, U.S. Pat. No. 3,439,938 issued to J. T. by Dunton on Apr. 22, 1969, also discloses a fire hydrant teaches the use of frangible structure to minimize impact damage. However, no developments have been directly made to create a compounded polymeric hollow shell to replace heavy ductile iron housings in residential application to solve attendant operational shortcomings unique to ductile iron residential and commercial fire hydrant shells. Also, no attempts have been disclosed to develop an inexpensive, lightweight, weather resistant colorfast compounded polymeric hydrant that can be placed over every existing commercially produced water control valve and residential water line. replace the metallic housings currently used to protect every existing commercially produced fire hydrant water control valve.
Existing hydrants are currently manufactured in a plurality of sizes and shapes specific to a particular manufacturers design and meeting all UL, FM, NFPA, and AWWA performance standards. Polymeric fire hydrants offer the necessary flexibility in manufacturing design and production to allow for the fabrication of all sizes and shapes of hydrants specific to any particular manufacturer and will also meet the UL, FM, NFPA, and AWWA performance standards.
Safety issues also come into play when reviewing the potential for property damage and personal injuries after a collision between a moving body and fixed metallic hydrant takes place. By utilizing a softer more impact resistant polymeric hydrant, the resultant damage to the hydrant or impacting object will be substantially mitigated. Most conventional metallic fire hydrants employ a standard design feature allowing for the hydrant to “give way” at the safety stem coupling as a result of a significant impact. Most impacts with a standard ductile hydrant, which are brittle in nature, render them un-repairable and requiring immediate replacement. A collision with the present polymeric invention will typically result in a shearing of the stem coupling and lower flange polymeric bolts, but will not require the replacement of the hydrant body nor expensive repairs to the impacting object.
The manufacturing of polymeric based articles is inherently more cost effective than the casting of articles from various metals. Plastics naturally lend themselves to higher volume and more cost effective production runs with higher yields of acceptable parts. Reasons for this include the low formulation costs, high throughput molding process and typically do not require the post casting finishing operations necessary in metal casting operations.
Plastic components are also inherently lighter than metallic components of the same design resulting in less labor and associated support equipment such as forklifts and lifting cranes. Typical back injuries resulting from the movement of heavy objects will be minimized.
In view of the foregoing, there is a need for a polymeric fire hydrant in residential and commercial, rural and metropolitan fire protection applications that can effectively mitigate the maintenance, performance and safety issues associated with metallic hydrants while simultaneously lowering manufacturing, installation and maintenance costs.